Properties and Applications

60si2mna strength hardness and elasticity hardenability steel is higher than 65, with a thermal sensitivity and tendency to temper brittleness, water quenching have to cracking tendencies. Cutting can still be annealed, cold plastic deformation is low, poor welding. By the middle of the plate spring load, diameter 7-20mm of coil spring and spring washer. Spring ring. High wear parts, such as grinding spindle of spring chuck. Precision machine screw. Cutter, spiral roller bearings on the rings. Railway rail and so on.

60Si2MnA low content of alloying elements, than 60Si2Mn high hardenability, toughness, ductility and higher, a small tendency to decarburization, tempering good stability, thermal processing performance and low cost. 60si2mna spring steel, manganese improve hardenability, φ12mm the hardenability of steel oil can, a small surface decarburization tendency than silicon, the mechanical properties after heat treatment is better than carbon steel, but overheating sensitivity and temper brittleness.

60Si2MnA production instead of heavy, medium and small cars, and other medium-sized cross-section of leaf spring leaf spring and coil spring. 60si2mna strength hardness and elasticity hardenability steel is higher than 65, with a thermal sensitivity and tendency to temper brittleness, water quenching have to cracking tendencies. Cutting can still be annealed, cold plastic deformation is low, poor welding. By the middle of the plate spring load, diameter 7-20mm of coil spring and spring washer. Spring ring. High wear parts, such as grinding spindle of spring chuck. Precision machine screw. Cutter, spiral roller bearings on the rings. Railway rail and so on.

Chemical composition

Carbon C: 0.52 ~ 0.60

Si Si: 1.5 ~ 2.0

Manganese Mn: 1.00 ~ 1.30

Sulfur S: ≤ 0.035

Phosphorus P: ≤ 0.035

Chromium Cr: ≤ 0.35

Ni-Ni: ≤ 0.35

Copper Cu: ≤ 0.25

Vanadium V: 0.08 ~ 0.16

Boron B: 0.0005 ~ 0.0035

Mechanical properties

Tensile strength σb (MPa): ≥ 1372 (140)

Yield strength σs (MPa): ≥ 1225 (125)

Elongation δ10 (%): ≥ 5

Reduction of area ψ (%): ≥ 30

Hardness: hot, ≤ 321HB; cold-drawn + heat treatment, ≤ 321HB

Standard heat treatment and microstructure

Standard heat treatment: quenching 860 ℃ ± 20 ℃, oil cooling; tempering 460 ℃ ± 50 ℃ (special needs, ± 30 ℃).

Microstructure: Tempered sorbite.

AC1-755, Ac3-770, Ms-300 ~ 305,

Annealing; 750C-furnace cold-HBS ≤ 222

Normalizing; 830 ~ 860C-cooled-HBS ≤ 302

Quenching; 870C-oil-HRC> 61

Temperature hardness after tempering HRC: 150C-61, 200C-60, 300C-56, 400C-51, 500C-43, 550C-38,

600C-33, 650C-29

Commonly used tempering temperature 430 ~ 480C, water or air, HRC45 ~ 50

The following are the parameters of car leaf spring heat treatment [1]

Quenching time and the thickness of insulation: mm / min, 6.5 / 2,8 / 3,8.5-10 / 4,12 / 5

Tempering holding time and thickness: mm / min, <10/25-30 ,10-15 / 30-35,15-20 / 40-45,20-25 / 45-50.

Delivery status: hot-rolled steel to heat treatment or heat treatment delivery, cold-drawn steel heat treatment to form